Making PDFs Accessible: A Complete Guide to PDF Accessibility

Over one billion people worldwide live with some form of disability. When you create a PDF that isn't accessible, you're potentially locking out a significant portion of your audience. In this comprehensive guide, you'll learn what makes a PDF accessible, why it matters, and which tools can help you get it right — including free options that respect your privacy.

What Is PDF Accessibility?

An accessible PDF is a document that can be read and navigated by everyone, including people who use assistive technologies like:

• Screen readers: Software like JAWS, NVDA, or VoiceOver that reads content aloud for blind or visually impaired users.
• Screen magnifiers: Tools that enlarge portions of the screen for users with low vision.
• Keyboard-only navigation: Users who can't use a mouse rely on keyboard commands to move through a document.
• Braille displays: Hardware that converts text into Braille characters in real time.

For a PDF to work with these technologies, it needs specific structural information embedded in the file — things like tags, reading order, and alternative text for images.

Why PDF Accessibility Matters

Legal Requirements

In many jurisdictions, digital accessibility isn't optional — it's the law:

• ADA (Americans with Disabilities Act): Requires accessible digital content for public-facing organizations.
• Section 508: U.S. federal agencies must produce accessible electronic documents.
• European Accessibility Act: Requires accessible products and services across the EU.
• WCAG 2.1: The Web Content Accessibility Guidelines provide the technical standard for digital accessibility, including PDFs.

Broader Reach

Accessible documents reach more people. Beyond users with permanent disabilities, accessible PDFs also help people with temporary impairments (broken arm), situational limitations (bright sunlight), or aging-related changes (declining vision).

Better SEO and Usability

Well-tagged PDFs with proper headings, alt text, and logical reading order are also easier for search engines to index and for all users to navigate.

Key Elements of an Accessible PDF

1. Document Tags (Structure Tags)

Tags are the backbone of PDF accessibility. They define the document's logical structure — headings, paragraphs, lists, tables, and figures. Without tags, a screen reader has no way to distinguish a heading from body text or understand the reading order.

Common tags include:

• <H1> through <H6> — Heading levels
• <P> — Paragraphs
• <L>, <LI> — Lists and list items
• <Table>, <TR>, <TD>, <TH> — Table structures
• <Figure> — Images and graphics

2. Alternative Text for Images

Every meaningful image in a PDF should have alternative text (alt text) that describes its content. Screen readers read this text aloud so visually impaired users understand what the image conveys. Decorative images should be marked as artifacts so screen readers skip them.

3. Reading Order

The reading order determines the sequence in which a screen reader presents content. In a multi-column layout or a page with sidebars, the visual order might not match the logical order. A properly tagged PDF defines the correct reading sequence explicitly.

4. Document Language

Setting the document language tells screen readers which pronunciation rules to use. A PDF marked as English will be read with English phonetics; a French document will use French pronunciation. This small setting makes a huge difference in comprehension.

5. Accessible Tables

Tables need proper header cells (<TH>) associated with data cells so screen readers can announce what each number or value represents. Without this, a table becomes an incomprehensible grid of disconnected values.

6. Bookmarks and Navigation

Longer documents should include bookmarks that map to the heading structure, allowing users to jump directly to specific sections. This is the PDF equivalent of a clickable table of contents.

How to Check PDF Accessibility

Before sharing a PDF, check its accessibility using these approaches:

• Check for tags: Use the PDF Info tool → to inspect whether your PDF has structure tags. If the "Tagged" property is "No," the document likely isn't accessible.
• Review metadata: The PDF Metadata tool → lets you check and set the document language and title — both essential for accessibility.
• Test with a screen reader: The most reliable test is to actually use a screen reader (NVDA is free for Windows) and navigate the document. Can you understand the content without seeing it?
• Use automated checkers: Adobe Acrobat Pro has a built-in accessibility checker. The free PAC (PDF Accessibility Checker) is another excellent option.

Tips for Creating Accessible PDFs

1. Start accessible: If you're creating a PDF from Word or another editor, use built-in heading styles, add alt text to images, and use proper list formatting before converting to PDF.
2. Don't rely on color alone: Information conveyed through color (like red = bad, green = good) should also be conveyed through text, patterns, or icons.
3. Use sufficient contrast: Text should have a contrast ratio of at least 4.5:1 against its background.
4. Make links descriptive: "Click here" is unhelpful. Use descriptive link text like "Download the accessibility checklist" so users know where the link leads.
5. Avoid scanned-only PDFs: Scanned pages are just images — completely inaccessible to screen readers. Use the OCR tool → to add a searchable text layer.

Common Accessibility Mistakes

• No tags at all: The most common issue. Without tags, the PDF is essentially opaque to assistive technology.
• Missing alt text: Images without descriptions are meaningless to screen reader users.
• Incorrect reading order: Content read in the wrong sequence can be confusing or nonsensical.
• Tables without headers: Data tables need explicit header-cell relationships.
• Missing document title: Screen readers announce the document title when opening a PDF. Without one, they read the filename instead.

Tools That Help

One23PDF offers several free tools that support accessibility workflows — all processing happens in your browser for complete privacy:

• PDF Info → — Check if a PDF has tags, metadata, and language settings
• PDF Metadata → — Set document title, author, and language
• OCR → — Add searchable text to scanned documents
• PDF to Text → — Extract text content for review or alternative format delivery

Making Accessibility a Habit

PDF accessibility doesn't have to be an afterthought. By building accessible practices into your document creation workflow — using heading styles, adding alt text as you insert images, and checking structure before exporting — you can produce accessible PDFs without extra effort. Your readers, all of them, will thank you.